A Quad-Band and Polarization-Insensitive Metamaterial Absorber with a Low Profile Based on Graphene-Assembled Film.

A quad-band metamaterial absorber using a periodically arranged surface structure placed on an ultra-thin substrate is demonstrated in this paper. Its surface structure consists of a rectangular patch and four L-shaped structures distributed symmetrically. The surface structure is able to have strong electromagnetic interactions with incident microwaves, thereby generating four absorption peaks at different frequencies.

N-Heterocyclic Carbene/Magnesium Cocatalyzed Radical Relay Assembly of Aliphatic Keto Nitriles.

An unprecedented N-heterocyclic carbene and magnesium cocatalyzed three-component acylcyanoalkylation of alkenes with cycloketone oxime esters and aldehydes is presented. This method displayed good scope generality, providing a transition-metal- and photoredox-free pathway to access various multifunctionalized aliphatic keto nitrile structures under mild reaction conditions. Moreover, this strategy is supposed to follow a radical relay mechanism via a single electron transfer event of a Mg/matched Breslow intermediate/oxime ester electron-donating acceptor (EDA) complex.

Application of isatin-derived saturated esters in the synthesis of 3,3'-spirooxindole γ-butyrolactams.

Stable while reactive isatin-derived saturated esters have been utilized as 3-carbon synthons in a base-promoted formal [3 + 2] annulation with N-Boc imines. The developed protocol offers a direct pathway for the rapid and divergent construction of two classes of 3,3'-spirooxindole γ-butyrolactam skeletons that are recognized as the privileged structures of various bioactive compounds. This protocol also has the advantages of mild reaction conditions, scalability and wide reaction scope.

Asymmetric Synthesis of C2-Quaternary Indolin-3-ones Enabled by N-Heterocyclic Carbene Catalysis.

An N-heterocyclic carbene (NHC)-catalyzed formal [4 + 2] annulation of 2-aryl-3 H-indol-3-ones with α,β-unsaturated carboxylic acids bearing γ-H was developed via an in situ activation strategy. The reaction involves the γ-addition of vinyl enolates to the unique cyclic ketimines to afford chiral tricyclic indolin-3-ones with a quaternary carbon center at 2-position. This protocol provides a rapid and enantioselective pathway to access a novel class of structurally important C2-quaternary indolin-3-ones that might be useful for drug discovery.

Orally bioavailable and brain-penetrant pyridazine and pyridine-derived γ-secretase modulators reduced amyloidogenic Aβ peptides in vivo.

Accumulation of amyloid β (Aβ) in brain is a pathological hallmark of Alzheimer's disease (AD). Aβ is generated after sequential cleavage of its parental molecule, amyloid precursor protein (APP), by β- and γ-secretases. Inhibition of γ-secretase activity is an effective approach for the reduction of Aβ levels.

Γ-secretase modulators do not induce Aβ-rebound and accumulation of β-C-terminal fragment.

γ-secretase inhibitors (GSIs) have been developed to reduce amyloid-β (Aβ) production for the treatment of Alzheimer's disease by inhibiting the cleavage of amyloid precursor protein (APP). However, cross-inhibitory activity on the processing of Notch can cause adverse reactions. To avoid these undesirable effects, γ-secretase modulators (GSMs) are being developed to selectively reduce toxic Aβ production without perturbing Notch signaling.

Confirmation of PSORS psoriasis susceptibility loci in a Chinese population.

We investigated 38 Chinese psoriasis families with 19 reported microsatellite markers. Families comprised a total of 96 affected and 92 unaffected individuals. Genotyping results were analyzed using parametric and nonparametric linkage analysis.

[Searching for the susceptibility loci of psoriasis in Chinese].

Objective: To search for the susceptibility genes of patients with psoriasis in Chinese.

Methods: 38 psoriasis families were determined to search for the susceptibility loci by selecting 19 reported polymorphic microsatellite DNA markers and making use of fluorescein-labeled PCR with Mega BACE sequencer.

Results: The significant two-point Lod score values of parametric linkage analysis were obtained with D6S1610 marker (1.